Test centurion Smith will miss the rest of the Rugby Championship in Australia and may not link up with the squad for their northern hemisphere tour, he said on Wednesday.

Smith's baby is not due until November but he was concerned he would not be able to return home because of the "increasing unlikelihood" of being allocated a spot in hotel quarantine as part of New Zealand's COVID-19 restrictions.

He will instead play in New Zealand's domestic NPC competition.

"The door isn't completely closed to me joining the (All Blacks) team for the northern tour if our baby comes early," the 32-year-old said in a statement.

"In this environment anything can happen so I've got an open mind.

"At the moment though, I just want to focus on being here with my family and enjoying that time and playing for Manawatu.

"I can't wait to get the boots on again."

After the Rugby Championship, New Zealand head to Washington to play the United States on October 23 before embarking on their season-ending tour of Europe.

Smith's absence will mean more chances for TJ Perenara, Brad Weber and Finlay Christie.

The All Blacks, who top the table with three straight wins, play their second match against Argentina in Brisbane on Saturday after their 39-0 win over the Pumas on the Gold Coast.

New Zealand lock Sam Whitelock also elected to stay home after the birth of his third child rather than join the squad for the Rugby Championship.

Australian Associated Press